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991.
Journal of Mechanical Science and Technology - This study applies image recognition technology to the shovel loading operation of a wheel loader for the first time. In the proposed method, the...  相似文献   
992.
Texture analysis and classification with tree-structured wavelettransform   总被引:57,自引:0,他引:57  
A multiresolution approach based on a modified wavelet transform called the tree-structured wavelet transform or wavelet packets is proposed. The development of this transform is motivated by the observation that a large class of natural textures can be modeled as quasi-periodic signals whose dominant frequencies are located in the middle frequency channels. With the transform, it is possible to zoom into any desired frequency channels for further decomposition. In contrast, the conventional pyramid-structured wavelet transform performs further decomposition in low-frequency channels. A progressive texture classification algorithm which is not only computationally attractive but also has excellent performance is developed. The performance of the present method is compared with that of several other methods.  相似文献   
993.
激光光斑探测系统软件设计与分析   总被引:1,自引:0,他引:1  
对激光光斑探测系统构成和光斑探测原理进行分析研究。在激光光斑探测系统软件设计中对图像采集控制和图像显示提出了全新的控制手段和设计思路,并对激光光斑采集软件和图像处理软件进行了详细设计说明,在图像处理软件设计中运用了一种激光光斑能量分布的三维伪彩色可视化方法,更加清晰反应光斑的不同区域能量分布的相对大小和位置。  相似文献   
994.
视景仿真技术应用研究   总被引:2,自引:0,他引:2  
概述视景仿真系统的软件系统和硬件系统基本组成,分析研究了软件系统中的一些关键技术问题,包括利用MFC实现分布式仿真、创建基于MFC的Vega SDI仿真程序、OpenGL回调函数、纹理映射建模等.提出了视景仿真的建模流程.采用了Vega渲染环境,用于实时视觉模拟的定义和场景的描述,选用编程工具Visual C ,进行视景仿真的调试.扩展了视景仿真技术在军事研究领域的应用,将对提高未来武器装备的性能和研制效率产生一定的影响.  相似文献   
995.
在28 nm低功耗工艺平台开发过程中,对1.26 V测试条件下出现的SRAM双比特失效问题进行了电性能失效模式分析及物性平面和物性断面分析.指出失效比特右侧位线接触孔底部空洞为SRAM制程上的缺陷所导致.并通过元素成分分析确定接触孔底部钨(W)的缺失,接触孔底部外围粘结阻挡层的氮化钛(TiN)填充完整.结合SRAM写操作的原理从电阻分压的机理上解释了较高压下双比特失效,1.05 V常压下单比特不稳定失效,0.84 V低电压下失效比特却通过测试的原因.1.26 V电压下容易发生的双比特失效是一种很特殊的SRAM失效,其分析过程及结论在集成电路制造行业尤其是对先进工艺制程研发过程具有较好的参考价值.  相似文献   
996.
Due to the rapid development of mobile devices equipped with cameras, instant translation of any text seen in any context is possible. Mobile devices can serve as a translation tool by recognizing the texts presented in the captured scenes. Images captured by cameras will embed more external or unwanted effects which need not to be considered in traditional optical character recognition (OCR). In this paper, we segment a text image captured by mobile devices into individual single characters to facilitate OCR kernel processing. Before proceeding with character segmentation, text detection and text line construction need to be performed in advance. A novel character segmentation method which integrates touched character filters is employed on text images captured by cameras. In addition, periphery features are extracted from the segmented images of touched characters and fed as inputs to support vector machines to calculate the confident values. In our experiment, the accuracy rate of the proposed character segmentation system is 94.90%, which demonstrates the effectiveness of the proposed method.  相似文献   
997.
Fractal image coding is an effective method to eliminate the image redundancy through piecewise self-transformability. The fractal code consists of a set of contractive affine transforms. To improve the performance when a range block experiences large error, we usually partition the range block into square or nonsquare subrange blocks for two- or multilevel fractal coding. In this paper, we find an inherent property of fractal coding that can be used to decide the edge orientation of a range block. Then this property is used for shape-adaptive fractal coding (SAFC). In SAFC, the top-level range block is partitioned into square or nonsquare (rectangle or triangle) subrange blocks for multilevel fractal encoding. Here, the maximum size of the range block can be the same as that of the whole image size while the minimum size is 4×4. In SAFC, no additional computations are required to obtain the edge orientation of a range block. Instead, we propose an edge-orientation detector, where the edge orientation of a range block is obtained during the fractal encoding process. According to our simulation results, SAFC can reduce the bit rate requirement of the conventional fractal coding scheme.  相似文献   
998.
李阔 《现代电子技术》2007,30(15):158-160
PCI总线是先进的高性能32/64位局部总线,是应用最广泛的微机总线标准之一。讨论了以CH365作为接口芯片的PCI总线接口卡的设计方法,并给出了一个ISA总线接口卡快速改造为PCI总线接口卡的实例。在设计中使用了CH365芯片特有的本地硬件地址请求功能及双口RAM读写的仲裁技术。设计的PCI接口板实现了预定的功能,具有较强的实用性和较高的市场推广价值。  相似文献   
999.
The relationship between investment in research and development (R&D) and firm performance has been the subject of numerous academic investigations, but the findings of these investigations have varied greatly, with research revealing a number of different patterns in the R&D–performance relationship. This inconsistency may be partly attributable to the failure of the commonly used linear modeling method to capture the full dynamics of the R&D–performance relationship. Based on the sigmoid (S) curve paradigm, as well as on other economic foundations, this study proposes the use of a three-stage S-curve model to help reconcile the disparities in the literature. This S-curve model shows that the relationship between R&D intensity and firm profitability is nonlinear, with the slope negative at low levels (stage 1), positive at medium levels (stage 2), and negative again at high levels of R&D investment (stage 3). Empirical evidence from a sample of 377 publicly listed Taiwanese high-tech manufacturing firms and 179 nonhigh-tech firms, examined during the period between 2000 and 2007, confirmed our proposed model. This study not only establishes a relationship pattern that differs from that shown in past studies, but also has important managerial implications for R&D managers and important policy implications for governments.   相似文献   
1000.
BCl3+CHF3 gas mixtures for the reactive ion etching process were applied to the gate-recess for fabricating (Al0.3Ga0.7)0.5In0.5P quaternary heterostructure double doped-channel FET's (D-DCFET), where a high uniformity of Vth was achieved. With the merits of this wide bandgap (Al0.3Ga0.7)0.5In0.5P layer, microwave power performance of this heterostructure D-DCFET demonstrates a compatible performance for devices fabricated on AlGaAs/InGaAs heterostructures  相似文献   
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